Some vendors decide to use a strict duplicate filter policy that only
filters on Bluetooth device addresses. This means that when the RSSI
changes, these devices are not reported again. During discovery it is
useful to actually get the RSSI updates.

Since this is specific to each controller, add a new quirk setting
that allows drivers to tell the core what kind of filtering policy
the controller uses.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>